Carburetor



Nov., 1 1 1924,

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S. B. SHAW CARBURETOR Filed June 5.

, following to be a full, clear, concise,V and Patented Nov, `lll, 11224..

erster In B. SHAW, OF SAN FRANCESC@ CALIFORNIA.

i caminamos.

Application nled June 3,

T0 all whom it may concern.'

Be it known that l, SIDNEY B.'SHAW, a citizen of the United States,.and a resident of the cit and countyof San Francisco, State of lalifornia, have made a new' and useful inventione-to' Wit, Improvements in C'arburetors; and l do hereby declare the exact description of the same.

rlhis invention relates particularly to carburetors for internal combustion engines. Among the objects of the invention are to convert hydrocarbon `fuel, ysuch as gasoline, distillate, kerosene, tops and the like' into fuel that will readily ignite and burn cleanly in internal combustion engines.- A' further object is to provide an yautomatic regulating and controlling mechanism for maintaining constant or an approximately constantratio between the fuel admitted to the intake and the engine' speed; an'd to cut'oi1 flow of fuel to the nozzle of the carburetor when engine is not in operation; to provide an improvedmeans for heating the liquid fuel and to increase itsvolatility; and to provide an improved carburetor for the utilization of low grade fuels that will be simple in construction, easy to manufacture, and eii'ective for the purpose for which it is designed. Further objects and advantages will appear as this description advances.

ln this specification and the annexeddrawings, the invention is illustrated in the form considered to be the best but it is to be understood that the invention is not limited to such form because it may be embodied in other forms, and it is also to be understood that in and by 'the claim following' the description, it isdesired to cover the invention in whatsoever form it may be embodied. ln lthe accompanying one sheet of vdrawins tdigure 1 represents'a vertical cross section through a carburetor constructed in 'accordance with my invention.

Fgure 2 is a section 'taken 1 on the `ine 2-2 thereon. y in detail the construction illustrated in the 4drawings includes a carburetor general ly designated by the numeral 1, having an air passage 2 therethrough registering with 'through Fig.

' the neck 3, and joined'thereto by the ange .The neck 3 is provided with the usual buttertly valve (not shown? fer the purpose 'of controlling the lvolume of mixture 1920. Serial N0. 386,220.

mitted to pass into the engine cylin ers. The body of the air passage'is provided with an integral web extension 5 connected to the'loat chamber 6 having a cork or metallic lloat member 7 slidably positioned therein on the central shaft 8, having'th'e end thereof bevelled to seat in an opening 9 of the conduit 10 through which hydrocarbon fuel of a .combustible nature is supplied` from a suitable source or reservoir not shown.

.The interior of the air passage 2 is con- 'stricted to form the usual `Venturi tube.

Within the said air passage and adjacent the 'constricted opening a fuel nozzle 12 formed of copper or other good heat conductor and of any standard design or type,

having the central bore 13 therein, and 1s concentrically mounted on an extended projection 14Y passing through the outer Walls of the air passage and passing into an extraneous heating means such as a by-pass pipe 15 from either the exhaust iiianifold or the radiator system. The end-of the projection 14 is provided with a tubular terminus 16 presenting a large, supercial'area for contact with the heated exhaust gases or the heated cooling medium of the radiator. Thus hot gases and the like, contacting with and passing through the member 16and that part. of the extension 14C exposed, will raiseits inherent temperature to substantially the same temperature as the heating medium and by conduction the heat will travel to the unheated portions of the member 14C gradually heating the fuel noazle 12 within the intake passage 2, The cuter exposed surfaces of the fuel nozzle 12, and extension 14 within the air passage 2 and where it passes throu the air passage walls, are provided wit an enclosing heat insulation coating li, such as mica, for the purpose of retaining the conducted heat within the fuel nozzle and its gapl '20, having the central bore 22 theretnrough,

adapted te be positioned in threaded engagement with the lower the 12, ,as at 21, and axially aligning with the central bore 13 provided in the fuel nozzle 12. The hollow pipe plug 23 is detachably mounted within the -hollowenlargement 19 adjacent the bushing 20, and is provided with a lateral aperture 24 passing into the central opening 25 in concentric relation with the aligned bores 13 and 22. The web 18 is providedl with the conduit 26 aligning with the aperture 24 and extending-through the integral arm member 5 into the float chamber 6, Intermediate the float chamber `6 and airpassage 2 the casting 5 is provided with a vertical extending projection 27 having the needle adjusting valve 28 slidably guided therein. The end 29 of the needle' valve 28 is bevelled and is adapted to seat onv a valve seat in the conduit 26, thus either stopping or controlling the amount and volume of liquid fuel admitted to the fuel nozzle 12.

The needle va%ve 28 is automatically op.

erated in the fol owing manner:

An elliptically shaped valve 30 is positioned transversely across the intake passage 3 and fixedly mounted on a shaft 31 having the ends 32 and 33 thereof rotatably mounted in suitable bearings 34 and 35 respectively on opposite sides of casting 3. The

end 33 of the said shaft is provided with a cam member 37 rigidly ositioned thereon. This cam comprises a su stantially annular disc having one-half the periphery thereof struck from the same radius and the remaining half struck from a greater radius vto proforked yoke 44, pivotally engaging the,v

needle valve 28 at 45, has the end 46 thereof, fixedly positioned on the cross rod 43 intermediate the extended bearings 34 and 35.

The needle valve 28 is operated in the following manner: i

The engine in its operation, .supposing it to be of multicylinder type, by the movement of the pistonswithin the cylinders creates a-suction on the downward stroke that has an ndrawin action u on any carburetted air centaine within e passage 3. The

sucking action of the pistons 1s approxirly holding, the valve 30- vnozzle 12'to be substantially on a level with Athat in the fioat chamber. Should the engine slow to idling speed and the suction action of the pistons gradually diminish, the position of the gate valve 30 within the passage 3 would likewise change, moving thecam 37 on the lever arm 41 to regulate the needle` valve 28 andthus supply a proportionate volume of fuel to the nozzle consistent with the speed of the engine. It will be obvious that by movement of the ordinary butterfly valve (not shown) controlled lby the hand or foot throttle of the operator, the amount of the carburetted air admitted to the cylinders can be cdntrolled to regulate the speed of the engine and when worked in conjunction with applicants automatic fuel controlling and regulating mechanism, the amount of fuel necessary to run the engine at slow speed will be automatically reduced.

Having thus described my invention what I claim and desire to secure by Letters Pat ent is:

A carburetor, comprisingin combination, a casing having an air passage therethrough; a fuel nozzle in said passage; a reservoir adjacent said casing for supplying fuel to said nozzle; 'a projection formed integrally with ysaid nozzle and extending outwardly through said casing; insulation surrounding the nozzle and projection and interposed between the nozzle projection and casing; a conduit adjacent said casing adapted to have heated fluid passed therethrough; and means on said projection terminating within said conduit, adapted to be heated by the fluid therein, whereby said projection and nozzle will be heated by conduction, and the heat of conduction transferred to the fuel in the nozzle. n

In testimon whereof, I have hereunto set my' hand at an Francisco, California, this 29th dayof May, 1920.

l SIDNEY B. SHAW. 

